It is well known in the art that the recoil of a gun is the result of two separate and distinct actions: the reaction due to the forward propulsion of the bullet itself and, upon the bullet reaching the muzzle end of the barrel, there is a further reaction due to instantaneous friction release between the bullet and gun barrel and the expansion of the gases exiting from the muzzle end of the barrel and, at least momentarily, at a velocity higher than the muzzle velocity of the bullet. However, because the time it takes for the bullet to travel from the breech end to the muzzle end of the barrel is relatively short, particularly in pistols or small arms, the recoil action due to the above factors is, to the shooter, essentially one. There has been much effort directed in the past towards producing muzzle brakes which reduce weapon recoil by controlling spent gases and such devices essentially fall into what may be categorized in two broad groups: those which seek to utilize the energy of the expanding gases which normally would produce a recoil to produce opposite reaction such as is disclosed in British Patent 454,533 and, in a second category, those devices in which the energy of the expanding gases is absorbed or dissipated interiorally of the muzzle brake so that what gases do escape through the muzzle end or downstream end of the weapon do not cause significant recoil such as Ashbrook Patent 3,492,912, and Tiffany Patent 2,499,428. While in some of these patents and the latter category have vents for venting gases to the atmosphere, they basically seek to achieve recoil reduction by providing surfaces interiorally of the brake for causing the expanding gases to swirl and impinge upon the themselves or on surfaces to cause a reaction opposing recoil or by providing large sound muffling chambers where the passage of the gases through the device is retarded by impingement or baffle walls. Others have compensators or muzzle brakes which have sophisticated shapes or structures which provide both recoil and sound absorbing features such as in Love Patent 1,259,251 and Strong Patent 2,667,815. Ruth Patent 3,155,003, operates on the theory of two different kinds or two types of gases created during the explosion of a propellant charge and seeks to provide a structure which deals with both types of gases in somewhat different ways.
In PCT Application Ser. No. PCT/US83/00984 there is disclosed an improved muzzle brake and the present application is a significant improvement on the device disclosed in that PCT application and the claims appended hereto are made in relation to that device.
As used herein, the term "spent" gas refers to those gases and burned, burning and unburned powder particles which escape from the muzzle after the bullet has separated from the muzzle of the gun.
Muzzle brakes according to the present invention include a tubular housing member which is an integral body preferrably cylindrical but not necessarily so. One end is bored with a relatively small diameter bore for a short distance into the body to form a first relatively small gas expansion chamber. The opposite end of the cylindrical body is bored with a substantially larger diameter bore to form a second volumetrically larger chamber which is substantially coaxial with the first volumetrically smaller chamber. This small diameter bore is of a short depth and terminates in spent gas impingement wall SB. The two chambers are separated by a relatively thick portion through which a bullet passage is bored and at a diameter which is at a predetermined degree larger than the bullet diameter. This middle bullet passage is approximately 50 percent longer than the one disclosed in the above PCT application and provides better stabilization. Since the bore diameter is larger relative to the bullet than in said PCT application, this longer passageway serves as a gas attenuator during and after the passage of the bullet from the volumetrically small chamber to the volumetrically large chamber, keeping in mind that the purpose of this invention is take advantage of the fact that the expanding gases have particles traveling at a higher velocity as they exit the muzzle than the bullet and therefore have, in the absence of thus muzzle brake, overtaken the bullet. A plurality of angulated apertures are formed in the upper half of the volumetrically small chamber and angled away from the muzzle barrel and the shooter and are of a size to accomodate the gases and serve to prevent the spent gases from kicking up dirt or sand in the face of the shooter while shooting from a tripod or prone position.
A plurality of tranverse slots are also formed in the upper surface of the body member in the volumetrically larger downstream chamber and these slots are made transverse to the longitudinal axis of the gun and provide larger openings for venting spent gas and, in conjunction with the openings in the volumetrically smaller chamber, provide better control and in the elimination of muzzle jump. Finally, the interior wall of the volumetrically larger chamber is threaded for threadably receiving the second component of the device, namely, a cone-shaped end or closure member which has, significantly, a very long bullet outlet passage which is of the same diameter as the middle bullet passage and thereby reducing manufacturing costs without sacrificing recoil reduction properties. This doubling of the length of the downstream bullet outlet passage causes significantly more of the spent gases to be vented to the atmosphere before the bullet leaves the muzzle brake. By the time the bullet has entered and fully traversed said outlet passage, substantially all spent gases will have been vented through the apertures. This results in better stabilization of the weapon and directing more of the blast away from the shooter when shooting from the hip position. Prior to the present invention, the shooter felt more of the concusion.
Accordingly, the object of the present invention is to provide an improved muzzle brake and more particularly, a muzzle brake having improved recoil reduction, stabilization and jump properties and, at the same time, having improved blast control properties directing the concusion and blast products away from the shooter.